Plaster guard



M. J. CAFIERO Feb. 21, 1950 PLASTER GUARD Filed Nov. 4, 1948 FIG. 2.

INVENTOR MICHAEL J. CAFIERO a I. v

Patented Feb. 21, 1950 UNITED STATES PATENT OFFICE PLASTER GUARD Michael J. Gafiero; RockyilleCe-ntre, N. Y. Application November 4, 1948;Serial No. 58,239

The invention herein disclosed relates to guards for protecting switch boxes, outlet boxes and the like against the entrance of plaster.

Objects of the invention are to provide a light,

inexpensive form of closure which may be quickly and easily applied to the opening-in a wall box cover and which while strong enough to resist plastering operations, will be of such nature that it maybe easily displaced and removed after the plasterhas dried. To facilitate the plastering. operations, these guardsfare preferably made flat and smooth and substantially flush with or slightly below the plaster line. As a result it frequently happens that a box will be completely plastered over and to that extent lost in the wall.

Special objects of the present invention are to overcome or eliminate this difliculty and to provide a plaster guard which will automatically mark the location of the box in the wall.

Other desired objects attained by the invention and the novel features of invention through which such results are accomplished are set forth or will appear in the course of the following specification.

The drawing accompanying and forming part of the specification illustrates one of the present commercial embodiments of the invention, but such illustration is primarily by way of disclosure, it being realized that structure may be modified and changed in various ways, all within the true intent and broad scope of the invention as hereinafter defined and claimed.

Fig. 1 in the drawing is a broken front elevation illustrating a wall box secured to the studding, door buck or the like and having a plaster guard applied to and closing the opening in the cover of the box;

Fig. 2 is a similar view showing the box completely plastered over and the plaster as marked to show the exact location of the plaster guard;

Fig. 3 is a broken vertical sectional view as on substantially the plane of line 3--3 of Fig. 2.

In Fig. 1 a box is indicated at 5 secured in its proper relation in a wall by a bracket 6 attached to the studding or other support 1.

This box has applied to it the usual cover 8 having an opening 9 for the mounting of a switch, outlet receptacle or the like.

Before plastering, the opening 9 is closed by a temporary cover l0 shown in the form of a flat plate of thin sheet metal slightly smaller than the opening, so that it may be pushed inwardly into the box and then be removed when it has 3 Qlaiins. (Cl. 220*3-4) served its purpose, and provided with inwardly hooked lugs I I at one end to engage over one edge of the opening, and inwardly angled lugs 12- at the opposite end to spring over the opposite edge of the opening.

Centrally disposed projecting lugs t3 at opposite ends of the plate serve the double purpose of holding the plate against inward displacement andof covering the screwholes M in the cover plate v8 to'prevent filling or clogging them with plaster.

The plate is easily engaged in the opening 9 by engaging the hooked "lugs 14 over one edge of the opening and then rocking the' -plate inwardlyon such lugs as pivots to force the beveled lugs l2 as spring catches inwardly over the edge at the opposite end of the opening.

These lugs hold the plate firmly enough in place for all ordinary plastering operations and do not interfere with bending in the plate at the center to push it inwardly out of the opening when the wall has dried and it is desired to gain access to the box for placing electrical fixtures and making circuit connections.

To enable quick removal of the plate from the box, it is shown as having a central opening 15 through which the finger may be inserted for pulling the plate out of the box.

For the purpose of indicating the location of a box which may have been completely plastered over, the guard plate is provided in the present disclosure with a marker which while not interfcring with plastering operations, will show through any plaster that may be applied over the same.

This marker consists in the present disclosure of a ring of plaster coloring material l6 on the outer'face of the plate about the opening l5.

This material is such as will penetrate an overlying layer of moist plaster. At present an acid dye dispersed by mechanical means in hydrocarbon resin dissolved in solvent is used. This dye is easily applied as by spraying or painting it on the face of the plate. It remains as a coating on the plate up to the time of installation in the wall; it is non-injurious to the hands; it shows up quickly in the wall immediately over the plate and is not dispersed through the plaster other than that immediately overstanding the plate and which is broken away and removed when the plate is broken in and removed from the box cover.

Fig. 2 shows how the marker appears on the finished face of the plaster as a ring of blue or other distinguishing color l1.

With a knowledge of the structure, the electrician may break in any overlying plaster directly over the center of the guard plate without unnecessarily cutting or breaking away any other plaster surface, and when removed the guard plate leaves the screw openings clean and open, ready to receive the screws for mounting the wall plate Or other finishing structure that is to be applied to the box. The opening in the guard plate serves to define and limit the size of the opening in the marker ring l6 and hence affords an immediately recognizable indication on the wall surface.

What is claimed is:

1. A box location indicating plaster guard comprising a closure for the opening provided in the cover plate of a wall box, said closure having means for temporarily retaining it in position on such cover plate while plastering is being effected and provided with plaster penetrating coloring medium on the face of the same which will show through an overlying layer of plaster to designate position of the guard plate in the wall and hence the location of the box and cover plate to which the plaster guard is applied.

2. A box location indicating plaster guard comprising a closure for the opening provided in the cover plate of a wall box, said closure having means for temporarily retaining it in position on such cover plate while plastering is being effected and provided with means which will show through an overlying layer of plaster to designate position of the guard plate in the wall and hence the location of the box and cover plate to which the plaster guard is applied, said marking means in eluding an acid dye dispersed in hydrocarbon resin dissolved in solvent applied to and carried by the outer face of the closure.

3. A box location indicating plaster guard comprising a closure for the opening provided in the cover plate of a wall box, said closure having means for temporarily retaining it in position on such cover plate while plastering is being effected and provided with means which will show through an overlying layer of plaster to designate position of the guard plate in the wall and hence the location of the box and cover plate to which the plaster guard is applied, said guard having an opening therein and said marking means including coloring material on the face of said guard about said opening and reactive to plaster to thereby show through an overlying plaster layer as a ring of color the approximate size of said opening in the plaster guard.

MICHAEL J. CAFlZERO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Allen et a1 June 11, 1940 

